HUMAN IMPACT ON SOIL EROSION AND SEDIMENT YIELD IN NORTHERN SHAANXI, CHINA

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IMPACTS OF DIFFERENT TYPES OF LAND USE ON PROCESSES OF SOIL AND WATER LOSS OVER PURPLE SOIL SLOPELAND

ＳｌｏｐｅｌａｎｄａｍｅｌｉｏｒａｔｉｏｎａｎｄｕｔｉｌｉｚａｔｉｏｎｗｉｔｈｃｏｍｐｌｅｘａｇｒｏｆｏｒｅｓｔｒｙｓｙｓｔｅｍｒａｉｓｅｄｂｙＰｒｏｆｅｓｓｏｒＨｕａｎｇＢｉｎｇｗｅｉｗａｓｍａｉｎｌｙａｉｍｅｄａｔｉｍｐｒｏｖｉｎｇｓｌｏｐｅｌａｎｄｓｕｓｔａｉｎａｂｌｅｐｒｏｄｕｃｔｉｖｉｔｙｂｙｕｓｉｎｇｂｉｏｌｏｇｉｃａｌｍｅａｓｕｒｅｓｆｏｒｔｈｅｐｕｒｐｏｓｅｏｆｐｒｏｖｉｄｉｎｇｎｅｗｍｅｔｈｏｄｆｏｒｆｕｔｕｒｅｃｏｍｐｒｅｈｅｎｓｉｖｅｅｘｐｌｏｉｔａｔｉｏｎａｎｄｕｔｉｌｉ…     

THE INFLUENCE OF FERTILIZERS, NaHCO3,SOIL TYPE ON CHEMISTRY OF FLOODED SOILS AND RICE PLANT GROWTH

1 INTRODUCTIONQuality of chemical properties of flooded soils isgenerally determined by salinity and alkalinity,bothof these acts as inhibiting factors of plant growth.Thecorrelation of electrical conductivity and other analysisindex has been reported by …     

COMPARISON OF THE ALKALI MARSH SOIL ANDAGRICULTURE SOIL ON NUTRIENT RETENTIONIN WESTERN JILIN, CHINA

An intact alkali marsh soil (MS) core and an agriculture soil (AS) core were studied by the simulated test in order to get the comparison of the nutrients retention in alkali MS and AS. The soil cores extracted from the Xiang-hai Wetland, western Jilin Province, China, were leached with solution contained carbon, nitrogen and phosphorus. Then the effluent water from the outlets of soil core with different depths was measured, including chemical oxygen demand (COD), total phosphorus (TP), phosphate (PO43-- P) and nitrogen existed as nitrate (NO3- - N), nitrite (NO2- - N) and ammonia nitrogen (NH4+- N) and the total nitrogen (TN) in the effluent water. COD and TP are decreased with the depth, the changing trends of TN, NO3- - N and NH4+ - N contents are similar to COD and TP, whereas NO2- - N in both MS and AS effluent have a little transition at 40cm depth. It is similar efficiency of MS to AS in significantly cutting down COD, TP, PO43- - P, TN, NO3- - N, NH4+ - N and NO2- - N in nutrient water. The fun     

DESERTIFICATION IN CHINA: STATUS, TRENDS, AND STRATEGIES

boncati0uofDcsendcahoninchhaboenificationisoneofthem0stseriotisenvirorunedlissuesoneafth.TheInteInaonalConedontoC0mbatbeeftifiCationswtinforberl994addressed[4]thadeSenificationislandhardation,resultingfromvariousfaders,indudingdiInaticvariationsandhuInana…     

REGIONAL DIFFERENTIATION OF CRITICAL CONCENTRATION OF ARSENIC(As) AND CADMIUM (Cd) IN MAIN SOIL TYPES OF CHINA

1CriticalconcentrationofpollutedheaVyn1etalsish1eallowableconcel1trationofheavymetalsinsoilsItisnotonIythecriticalindexofvanousbiologicalandenvironmentalehaofmetalelementsinsoils,blltalsothebasisforworkingoutti1estandardofsoilenvirorunatalquality,anddefilungthesoilenvironn1entalconcentration.Attentionwasthuspaidtoenvironmotalconservationathomeandabroad.Althoughtherearen1anyrePorts[2-4]oneffeCtsofsinglesoilpollutant,yCttherearefewrePoftsoncompansonsofn1etalelema1tcnticalconcatrationinsoilsofd…     

CONDITION NUMBERS, ITERATIVE REFINEMENT AND ERROR BOUNDS

Concentration estimates of components present in a sample mixture can be obtained using matrixmathematics. In the past, the condition number of the calibration matrix has been used to give anamplification factor by which uncertainties in data can work through to errors in the concentrationestimates. This paper explores an additional interpretation of condition numbers with regards tosignificant figures and rounding errors. A procedure is suggested which will always give the most accurateconcentration estimates provided the calibration matrix is not too ill-conditioned. Condition numbershave also been used by analytical chemists to discuss the error bounds for concentration estimates.Unfortunately, only one representative error bound can be approximated for all the components. Thispaper will show how to compute bounds for individual concentration estimates obtained as solutions to asystem of m equations and n unknowns. The procedure is appropriate when calibration data and sampleresponses are inaccurate.     

WHAT'S IN A NAME? LINGUISTICS,GEOGRAPHY, AND TOPONYMS*

In differing ways, linguistics and geography each observes that a name's significance is connected to a society. According to lexical theory, a word is arbitrary: Its sound and meaning have no intrinsic link; its function is grammatical. Names are, however, special words. We bestow names based on how they sound or on what they may already have come to represent; names are not arbitrary. In turn, toponyms are special names, and as example we discuss a specific one, “New Orleans.” Far from an arbitrary pairing of form and meaning, this toponym reveals that names reflect the experience of the people who use them.     

URBAN GROWTH, TRANSPORTATION SYSTEM AND COMMERCIALNETWORK OF BEIJING

Behing(N0rthCapital)issituatedatthenoItl1emextren1ityoftheNortl1ChinaPlainandl40kintoitssoutheaststretcllesh1eB0haiSea,aninlandseaofPacific.ItisshLifinbymoUntainsonthenortheast,nortl1andwest.Threerivers0fYongding,WenyuandChaobaiflowacrossh1ecounrysidetoth…     

ON ECOLOGICAL CHARACTERISTICS, UTILIZATION AND MANAGEMENT OF THE TIBETAN PLATEAU, CHINA

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AN OCCURRENCE OF THE ASSEMBLAGE GRANDIDIERITE, KORNERUPINE, AND TOURMALINE IN ANTARCTICA

Grandidierite, kornerupine, and tourmaline occur in high-grade pelitic gneisses from the Larsemann Hills, East Antarctica. The three minerals contact to each other and show a special order: Trn_1→Gdd→Trn_2→Krn→Trn_3, suggesting the occurrence of the assemblage is controlled by the temporal changes of the chemical potentials of B_2O_3 and H_2O. The discovery of the assemblage is a good constraint on the seting and composition feature of metamorphism in the area.     

EFFECT OF CARBON AVAILABILITY ONMICROBIAL ACTIVITIES IN Calamagrostis angustifolia SOIL

Carbon availability varies very much along soil profile and decreases from topsoil to subsoil. The effect of carbon availability index (CAI) on microbial activities in Calamagrostis angustifolia soil in the Sanjiang Plain in the Northeast China was measured. Based on the proposal about CAI and microbial respiration from Parkinson and Coleman (1999), the results showed that carbon availability limits the microbial activities in topsoil, root layer soil and subsoil initially, wbercas it does not limit the microbial activity after 1.5 h incubation for recovery from the disturbance inphysical, chemical and biology structure resulting from sampling, then after 5h incubation carbon availability limits mierobial activity again after the labile carbon was mineralized. At the same time the soil organic matter affects the carbon availability significantly when it is lower than 10%, but little when the soil organic matter is higher than 10%. The microbial biomass carbon is linearly related to carbon availability in the Calamagrostis angustifolia soil. When the CAI is lower than 0.85, the β-glucosidase activity increases along with CAI, but decreases when CAI is larger than 0.85.     

DEPOSITIONAL CHARACTER AND SHORELINE CHANGES OF THE NANDUJIANG DELTA,HAINAN ISLAND,CHINA

.Introducti0nTheNandujianghiver,withalengthOf3llkIn,adrainageareaof684lkm2andanaverageannunldischargOf60xl09m',isthelargstriveronHainanIsland.IttransportsanaveragannualsedimentloadOfO.68xlO6tonsnorthwdintoQangrhouStrait,wherethetidalrangnisca1.Om,andwavesandlongrhorecurrentsarerelativelystrong.TheNandujiangdeltacoves20OkIn2.ThedePOsitionalSystemOfthedeltaconsistsofrivermouthbars,distribotarymouthbars,marshdepositsfOrmedinbaysandlagoons,sandridges,sandsPitsanddunes.ThedistributionPatt…     

SOIL SALINITY CONTROL REGARDING SUBSURFACE WATER REGULATION IN NORTH CHINA PLAIN

IIntroductionLocatedinthesemi-hunudandsemi-aridroponsofeastemChina,theNorthChinaPlain(NCP)isoneofthelargesta1luvialp1ainsmChinawithanareaofabout38othousandkm.Ithasacontinedlmonsoonclimatewithanannualpredpitrionof8Oomminthesouthempartandreducingtoabout5OOmminthenorthem.ItfallsinthetyPicawarmteInPeratezonenddeciduousforestandsparseforest/shrubforest.Themainsoiltapesaredriamonsoils,brownsoilsandChaosoils(meadowsoils)affectedbygroundWateractivihesandlandcultiVation,indudingyellowmeadowsoil…     

SOIL SURVEYS AND TOPOGRAPHIC MAPS TO BE USED WITH SAMPLE AREAS DEPICTED IN THE LOOK OF OUR LAND—AN AIRPHOTO ATLAS OF THE RURAL UNITED STATES

Considering the influence of German geography on the historic development of the discipline in North America, surprisingly little communication takes place between German-speaking and English-speaking geographers today. This report is intended to provide readers of THE PROFESSIONAL GEOGRAPHER with a review of recent events in the German-speaking countries of Europe, giving special attention to ways in which ideological differences have influenced geographic research in the two parts of divided Germany. It also traces the emergence of theoretical-quantitative geography in German research, the rise of applied research, and recent trends in regional geography.     

QUATERNARY DIATOMS AND CYSTS FROM XIHU LAKE ON FILDES PENINSULA OF KING GEORGE ISLAND, ANTARCTICA AND THEIR PALAEOENVIRONMENTS

The Xihu Lake is Located on the southern Fildes Peninsula. A drill hole is 2.6 m deep and total 102 samples were collected by Dr. Xie Youyu during 1985-1986. The samples from drill hole in the Xihu Lake contain abundant and well-preserved diatoms and Cysts (Chrysophata), 131 species and variaties of diatoms belonging to 21 genera were reoognized. As a result of the detailed research on the diatom assemblages from the Xihu Lake sediments, 9 diatom assemblages were distinguished. From diatom and Cysts (Chrysophyta) data, the changes of the Palaeoenvironments and Palaeoclimate and their age are discussed.     

IMMIGRATION, GEOGRAPHIC DISTRIBUTION AND SOCIAL ECONOMIC STATUS OF AMERICAN CHINESE

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TEMPORAL AND SPATIAL ASPECTS OF BLOWING DUST IN THE MOJAVE AND COLORADO DESERTS OF SOUTHERN CALIFORNIA, 1973–1994

Although dust storms rarely occur in southern California's deserts, blowing dust often reduces visibility, and large spatial and temporal variability in the frequency of blowing dust occurs throughout the region. On average only 1.3 dust storms occur in the study area each year. The annual average number of dust events (visibility <11 km) is 18.0, with the Coachella Valley being dustiest region, averaging 37.8 dust events each year. Mean annual frequencies of dust events for 1973–1994 are mapped, showing a core of activity centered over the Imperial/Coachella Valley region, with fewer dust events around the periphery of the study area. Most stations show a coherent temporal pattern of dust frequency during the period 1973–1994, with the mid-1970s experiencing the most dust. Blowing dust generally was absent from all stations during 1979–1983, 1987–1989, and 1992–1994. The mid-1980s were moderately dusty and 1990–1991 saw a return to very dusty conditions, possibly resulting from below-normal precipitation and increased anthropogenic disturbances. Dust events in the Mojave Desert characteristically occur during the winter to spring months (February-May), associated with dry frontal activity, and are largely absent during the dry summer months. The Colorado Desert experiences a similar seasonal distribution of dust events, but has more summer events, usually associated with convective thunderstorms. Frequencies of blowing dust have weak, but statistically significant, correlations with mean annual and antecedent precipitation, suggesting that complex processes control dust emission. [Key words: blowing dust, dust storms, Mojave Desert, Colorado Desert, wind erosion.]